fish_key_bindings may be set directly
or via fish_{default,vi}_key_bindings.
The latter use "set --no-event" to simplify their control
flow. This (24836f965 (Use set --no-event in the key binding
functions, 2023-01-10)) broke Vi mode cleanup, since Vi mode
uses a variable hook. Let's update this variable also when using
fish_{default,vi}_key_bindings. Another reason to keep this variable
in sync is to make the fish_key_bindings handlers working as expected.
